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371.
Analysis of a regenerative braking system for Hybrid Electric Vehicles using an Electro-Mechanical Brake 总被引:3,自引:0,他引:3
J. K. Ahn K. H. Jung D. H. Kim H. B. Jin H. S. Kim S. H. Hwang 《International Journal of Automotive Technology》2009,10(2):229-234
The regenerative braking system of the Hybrid Electric Vehicle (HEV) is a key technology that can improve fuel efficiency
by 20∼50%, depending on motor size. In the regenerative braking system, the electronically controlled brake subsystem that
directs the braking forces into four wheels independently is indispensable. This technology is currently found in the Electronic
Stability Program (ESP) and in Vehicle Dynamic Control (VDC). As braking technologies progress toward brake-by-wire systems,
the development of Electro-Mechanical Brake (EMB) systems will be very important in the improvement of both fuel consumption
and vehicle safety. This paper investigates the modeling and simulation of EMB systems for HEVs. The HEV powertrain was modeled
to include the internal combustion engine, electric motor, battery and transmission. The performance simulation for the regenerative
braking system of the HEV was performed using MATLAB/Simulink. The control performance of the EMB system was evaluated via
the simulation of the regenerative braking of the HEV during various driving conditions. 相似文献
372.
H. -D. Kang D. -H. Kim S. -W. Chae J. -N. Han D. -S. Kim 《International Journal of Automotive Technology》2009,10(5):583-587
Most of the research on safety belt systems has involved crash simulation that only considered a dynamic human model. However,
belt routing analysis, usually known as comfort level estimation, is also an important factor in safety belt design, considering
that serious injuries of the abdominal region result from the infiltration of a belt into the neck or the chest. Thus, safety
belt evaluations using kinematic human models are also needed. In this paper, a belt fit simulation method is suggested. Using
the proposed process, both comfort and safety analyses can be performed under the same conditions continuously, and thus the
safety belt design parameters, such as the location of anchor points, dummy posture and etc., can be evaluated. In conclusion,
this computer process enables a belt system design to reduce injuries. 相似文献
373.
In this study, a parallel flow condenser and laminated evaporator for an automotive air-conditioning system were modified
to improve performance. Gas-liquid separation type condensers, in which the condenser and receiver drier are integrated, and
one-tank laminated type evaporators were developed, and their performances were investigated experimentally using HFC-134a.
Heat transfer characteristics in the condenser are examined by means of air temperature, air velocity entering the condenser
and inlet pressure of the refrigerant; heat transfer characteristics in the evaporator are examined by means of air temperature,
relative humidity, flow rate of air, outlet pressure of refrigerant and superheat. Pressure drops for both evaporator and
condenser are also measured, and correlations for pressure drop are derived for the condenser and evaporator, respectively.
Air velocity and mass flow rate of the refrigerant have a significant effect on the overall heat transfer coefficient, and
flow pass is not significantly influenced by the cooling capacity of the condenser. The overall heat transfer coefficient
of the evaporator increases as air flow rate, air temperature and relative humidity increases. 相似文献
374.
John C.Humphrey 《汽车与配件》2006,(6):18-19
汽车产品的质量总是会受到巨大的关注。质量较差会导致财务成本的增加,这使得制造商把提升质量作为一项商业必要的手段。过去的数年中有无数方法和流程被用来减少浪费和消除缺陷 (比如6-Sigma法和TQM完全质量管理法)。我们并不缺少这样的衡量工具,来衡量因质量问题和返工而产生的负面经济效益。运用这些衡量工具能够理解质量对每辆车或者公司的盈利能力造成的影响,并且帮助公司取得显著的产品质 相似文献
375.
The existing maintenance strategies of offshore wind energy are reviewed including the specific aspects of condition-based maintenance, focusing on three primary phases, namely, condition monitoring, fault diagnosis and prognosis, and maintenance optimization. Relevant academic research and industrial applications are identified and summarized. The state of art, capabilities,and constraints of condition-based maintenance are analyzed. The presented research demonstrates that the intelligent-based approach has become a promising solution for condition recognition, and an integrated data platform for offshore wind farms is significant to optimize the maintenance activities. 相似文献
376.
This work investigated the influence of two types of mooring systems on the hydrodynamic performance of a two-body floating wave energy converter(WEC). It also investigated the effects of the physical parameters of the mooring system on the amount of extractable power from incident waves in the frequency domain. The modeled converter comprised a floating body(a buoy), a submerged body with two mooring systems, and a coupling system for two bodies. The coupling system was a simplified power take-off system that was modeled by a linear spring-damper model. The tension leg mooring system could drastically affect the heave motion of the submerged body of the model and increase relative displacement between the two bodies. The effects of the stiffness parameter of the mooring system on power absorption exceeded those of the pretension tendon force. 相似文献
377.
Journal of Marine Science and Application - The existing maintenance strategies of offshore wind energy are reviewed including the specific aspects of condition-based maintenance, focusing on three... 相似文献
378.
Jennifer D. Ruiz-Ramírez Jorge I. Euán-Ávila Víctor H. Rivera-Monroy 《Coastal management》2019,47(1):23-43
We evaluated the potential economic impacts of increasing sea level rise (SLR) along the Mexican Caribbean where there are major gaps in our understanding of the mechanisms controlling flooding duration and frequency associated to future ecological and economic impacts. We determined the negative economic impact of SLR on infrastructure in the largest urban centers (Cancun, Isla Mujeres, Playa del Carmen, Puerto Morelos and Cozumel) in the state of Quintana Roo (Mexico) that are considered the largest tourism “hot spots” (resort cities) in the country. The tourism industry in this coastal area injects >8 billion dollars year?1 to the Mexican economy. Our conservative economic assessment regarding the impact of SLR, under a 1?m scenario for all coastal cities is $330 million USD. Further projections for worst scenarios (SLR >2 m) show a non-linear trend where the cost of inaction can reach up to $1.4 billion USD (2?m SLR scenario) and $2.3 billion USD (3?m SLR scenario). This potential loss of infrastructure, as construction cost, is staggering and represents a robust baseline to start evaluating with more detail future impacts of climate variability and change on the Mexican Caribbean coastline. 相似文献
379.
380.
Patel Hersila H. Messiah Sarah E. Hansen Eric D’Agostino Emily M. 《Transportation》2021,48(5):2315-2333
Transportation - Transportation vulnerability, defined as lack of access to transportation resulting in financial, social, or health consequences, reduces quality of life. While research has... 相似文献